Recording medium with restricted playback feature and apparatus and methods for forming, recording, and reproducing the recording medium

ABSTRACT

A recording medium, such as a high-density and/or read-only recording medium, such as BD-ROM, capable of preventing unauthorized duplication of data streams, written thereon, onto another medium, such as a BD-RE or BD-R, which includes physical mark information, and to methods and apparatuses for forming, recording, reproducing, and restricting playback of the recording medium to prevent unauthorized duplication.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This U.S. nonprovisional application is a continuation of PCTInternational Application No. PCT/KR2003/001292 filed on Jul. 1, 2003,the entire contents of which are hereby incorporated by reference, whichfurther claims priority on Korean Patent Application No.10-2002-0037947, filed on Jul. 2, 2002 and Korean Patent Application No.10-2002-0054762 filed on Sep. 10, 2002, the entire contents of eachwhich are also hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a recording medium such asBD-ROM (Blu-ray Disc ROM) which has a capability to restrictunauthorized duplication of data written therein, which includesphysical mark information and an apparatus and methods for forming,recording, reproducing, and restricting reproduction of illegallyduplicated recording media.

[0004] 2. Description of the Related Art

[0005] Recently, standardization of new high-density rewritable opticaldiscs has rapidly progressed, for example, BD-RE (Blu-Ray DiscRewritable), which can store a large quantity of high-quality video andaudio data. As a result, products associated with such discs have alsobeen developed. Such products are expected to be commercially availablein the near future.

[0006] Referring to FIG. 1, the disc structure of a conventional BD-REis shown. As shown in FIG. 1, the BD-RE has a center hole and a clampingarea which are adapted to allow the optical disc to be loaded inposition in an optical disc apparatus. The optical disc also has aninformation area for recording disc management information and datathereon.

[0007] A lead-in area (LI), a data area, and a lead-out area (LO) areassigned to the information area. A burst cutting area (BCA) is assignedto the area preceding the lead-in area. The BCA, which is not a writablearea, contains information modulated into a format unique to BD-RE.

[0008] Referring to FIG. 2, an example of an optical disc apparatusapplicable to BD-RE is shown. As shown in FIG. 2, the optical discapparatus includes an optical pickup 10, a video disc recorder (VDR)system 11, and an encoder 12. The optical disc apparatus performs a datarecording operation for encoding and modulating data, externally inputthereto, into a format unique to BD-RE, and then recording the modulateddata on a data area assigned to the information area of the BD-RE. Theoptical disc apparatus also performs a data reproduction operation forreading out data recorded on the data area, and processing the read-outdata to reproduce original video and audio data.

[0009] The optical disc apparatus having the above-mentionedconfiguration can record audio/video (A/V) data of a movie orbroadcasted program on a BD-RE optical disc 100, and subsequentlyreproduce the recorded A/V data from the BD-RE optical disc 100 in theform of high-quality video and audio.

[0010] The development and standardization of high-density read-onlyoptical discs, such as BD-RE and its read-only counterpart, BD-ROM(Blu-ray Disc Read-Only Memory), and write-once Blu-ray discs such asBD-R (Blu-ray Disc Recordable) have recently been progressing. However,there is no effective solution for preventing unauthorized duplicationof data streams, written on a BD-ROM, or onto other optical discs, suchas BD-RE or BD-R.

SUMMARY OF THE INVENTION

[0011] In exemplary embodiments, the present invention is directed to arecording medium, such as a high-density and/or read-only recordingmedium, such as BD-ROM, capable of preventing unauthorized duplicationof data streams, written thereon, onto another medium, such as a BD-REor BD-R, and to methods and apparatuses for forming, recording,reproducing, and restricting playback of the recording medium to preventunauthorized duplication.

[0012] In exemplary embodiments, the present invention is directed to arecording medium, such as a high-density and/or read-only recordingmedium, such as BD-ROM, capable of preventing unauthorized duplicationof data streams, written thereon, onto another medium, such as a BD-REor BD-R, which includes physical mark information and to methods andapparatuses for forming, recording, reproducing, and restrictingplayback of the recording medium to prevent unauthorized duplication.

[0013] In an exemplary embodiment, the present invention is directed toa recording medium including recorded data, the recording mediumincluding an information area for recording disc management informationand/or data, the information area includes a lead-in area, a data area,and a lead-out area and physical mark information, recorded as a wobbledpit pattern in an area preceding the lead-in area, in the lead-in area,in the data area, in the lead-out area, or in an area following thelead-out area of the information area.

[0014] In another exemplary embodiment, the present invention isdirected to a method of forming a recording medium, including forming aninformation area for recording disc management information and/or data,the information area includes a lead-in area, a data area, and alead-out area and forming physical mark information as a wobbled pitpattern in an area preceding the lead-in area, in the lead-in area, inthe data area, in the lead-out area, or in an area following thelead-out area of the information area of the information area.

[0015] In another exemplary embodiment, the present invention isdirected to a method of reproducing data from a recording medium,including utilizing physical mark information to control reproduction ofthe recorded data, wherein physical mark information has been recordedas a wobbled pit pattern in an area of the recording medium

[0016] In another exemplary embodiment, the present invention isdirected to a method of recording data on a recording medium, includingrecording the data in an information area, which includes a lead-inarea, a data area, and a lead-out area and recording physical markinformation as a wobbled pit pattern in an area of the information area,which controls reproduction of the recorded data.

[0017] In another exemplary embodiment, the present invention isdirected to an apparatus for reproducing data from a recording medium,the apparatus utilizing physical mark information to controlreproduction of the recorded data, wherein the physical mark informationhas been recorded as a wobbled pit pattern in an area of the recordingmedium.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Features and advantages of the exemplary embodiments of thepresent invention will become more apparent after reading the followingdetailed description when taken in conjunction with the drawings, inwhich:

[0019]FIG. 1 is a diagram illustrating the disc structure of aconventional BD-RE;

[0020]FIG. 2 is a schematic block diagram illustrating the configurationof a conventional BD-RE recorder;

[0021]FIG. 3 is a diagram illustrating the disc structure of a BD-ROMaccording to an exemplary embodiment of the present invention;

[0022]FIG. 4 is a schematic view illustrating physical discidentification information recorded in the form of a wobbled pit patternin accordance with an exemplary embodiment of the present invention;

[0023]FIG. 5 is a diagram illustrating the disc structure of a BD-Raccording to an exemplary embodiment of the present invention;

[0024]FIG. 6 is a schematic view illustrating physical discidentification information recorded in the form of aligned pit stringsin accordance with an exemplary embodiment of the present invention;

[0025]FIG. 7 is a table for comparing data recording formats of BD-ROM,BD-RE, BD-R, and BD-R for authoring;

[0026]FIG. 8 is a schematic block diagram illustrating the configurationof an optical disc apparatus to which a playback restricting methodaccording to an exemplary embodiment of the present invention isapplied; and

[0027]FIGS. 9a and 9 b are flow charts illustrating sequential processesof the playback restricting method carried out in the optical discapparatus in accordance with an exemplary embodiment of the presentinvention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0028] Hereinafter, exemplary embodiments of a recording medium, such asa high-density and/or optical disc according to the present invention,and an apparatus and a method for forming, recording, reproducing, andrestricting playback of the high-density optical disc in accordance withthe present invention will be described in detail with reference to theattached drawings.

[0029] Referring to FIG. 3, the disc structure of a BD-ROM according toan exemplary embodiment of the present invention is shown. As shown inFIG. 3, the BD-ROM 200 has a center hole and a clamping area which areadapted to allow the BD-ROM 200 to be loaded in position in an opticaldisc apparatus. The BD-ROM 200 also has an information area on whichdisc management information and data have been recorded.

[0030] A lead-in area (LI), a data area, and a lead-out area (LO) may beassigned to the information area. A disc identification area, forexample, a ‘BD-ROM identification (ROMID)’ area, can be assigned to thearea preceding the lead-in area (LI). The ROMID area may correspond tothe BCA of the BD-RE described with reference to FIG. 1. The ROMID areaalso can be assigned to a particular region of the lead-in (LI) orlead-out area (LO).

[0031] The ROMID area, which is not a writable area, may containidentification information indicating that the associated disc is of aBD-ROM type. This identification information can be modulated andrecorded into a format unique to BD-ROM, for example, a physical BD-ROMID mark.

[0032] As shown in FIG. 4, the physical BD-ROM ID mark can be recordedin the form of a wobbled pit pattern. The physical BD-ROM ID mark can bedetected at an initial stage of a servo operation, independent of adecoding operation for reproducing data. The wobbled pit pattern of thephysical BD-ROM ID mark can represent an encryption key value used inencrypting the data to be written on the data area, for example,duplication preventing information.

[0033] Data encoded and modulated into a format unique to BD-ROM isrecorded on the data area assigned to the information area. This data iswritten in a mastering process during the manufacture of the associateddisc.

[0034]FIG. 5 illustrates the disc structure of a Blu-ray write-once,that is, BD-R, in accordance with an exemplary embodiment of the presentinvention. As shown in FIG. 5, the BD-R 300 has a center hole and aclamping area which are adapted to allow the BD-R 300 to be loaded inposition in an optical disc apparatus. The BD-R 300 also has aninformation area for recording disc management information and datathereon.

[0035] A lead-in area (LI), a data area, and a lead-out area (LO) may beassigned to the information area. A disc identification area, forexample, a ‘BD-R identification (RID)’ area, also can be assigned to thearea preceding the lead-in area. The RID area may correspond to the BCAof the BD-RE described with reference to FIG. 1.

[0036] The RID area, which is a writable area, may containidentification information representing the fact that the associateddisc is of a BD-R type. The identification information can be modulatedand recorded into a format unique to BD-R, that is, a physical BD-R IDmark.

[0037] The physical mark can also recorded in the form of a wobbled pitpattern, as shown in FIG. 4. The physical BD-R ID mark can be detectedat the initial stage of a servo operation, independent of a decodingoperation for reproducing data.

[0038] The physical mark can also be recorded in the form of a pitpattern other than the wobbled pit pattern. Using a physical mark havinga pit pattern other than the wobbled pit pattern, it is possible towrite data on the data area in an encrypted state, and to decrypt theencrypted data read out from the data area. This is described in moredetail below.

[0039] Physical mark information, which is recorded on a desiredrecording area, for example, a lead-in area or a particular area (ROMIDor RID area) preceding the lead-in area, in a BD-ROM or a BD-R authoredfor manufacture of BD-ROM, can be written to have a pattern of repeatedmark/space pairs with respect to a monotone high-frequency-modulated(HFM) groove. Each mark/space pair may include a mark and a space eachhaving an optional length.

[0040] For example, as shown in FIG. 6, the physical mark informationmay be written with respect to a monotone HFM groove in which everyrecording field having a length of 36T has either a high level or a lowlevel, irrespective of the data sequence value of the physical markinformation. Where the data value of a 36T recording field is “1”, amark/space pair including a mark having a length of 3T (3Tm) and a spacehaving a length of 3T (3Ts) may be repeatedly recorded 6 times in the36T recording field to form a pattern of 6 aligned mark/space pairs.Where the data value of the 36T recording field is “0”, a mark/spacepair including a mark having a length of 9T (9Tm) and a space having alength of 9T (9Ts) may be repeatedly recorded 2 times in the 36Trecording field to form a pattern of 2 aligned mark/space pairs.

[0041] In the latter case, where the data value of the 36T recordingfield is “0”, a mark having a length of 12T (12Tm), a space having alength of 12T (12Ts), and a mark having a length of 12T (12Tm) may besequentially recorded in the 36T recording field. In this case, however,errors may occur during a tracking servo operation, because thefrequencies of RF and push-pull signals may be lowered due to the 12Tlength of the marks and space. In another exemplary embodiment, repeatedmark/space pairs are recorded each including a mark of 9T (9Tm) and aspace of 9T (9Ts) which are capable of maintaining respective RF andpush-pull signals at appropriate frequencies.

[0042] Where physical mark information is recorded to have a wobbled pitpattern, as described above with reference to FIG. 4, the wobbled pitscan be formed using mastering equipment adapted to manufacture BD-ROMs.However, such wobbled pits cannot be recorded in general disc drivers,for example, BD-R drivers, because the wobbling frequency is beyond thedriving frequency band of an actuator used in BD-R drivers. As a result,it is impossible to duplicate BD-ROMs, using BD-R drivers.

[0043] In other words, in a BD-R authored for manufacture of BD-ROM,that is, a BD-R for authoring, it is possible not only to recordphysical mark information, but also to record essential disc information(DI) to be permanently recorded and maintained in an area, such as apermanent information & control (PIC) data region included in thelead-in area of the BD-R, by applying a recording technique in whichrepeated mark/space pairs, each including a mark and a space, eachhaving an optional length, are recorded such that they are aligned withone another, with respect to a monotone HFM groove. On the other hand,recording of data in the writable area of the BD-R is achieved withrespect to each typical wobbled groove.

[0044] In the case of BD-ROM, wobbled pits or normal pits can berecorded in the area, such as the PIC region of the BD-ROM, whereas datahaving the form of general pit strings is recorded in the data recordingarea of the BD-ROM. Accordingly, optical disc apparatuses can moreeasily distinguish the type of any optical disc, for example, BD-RE orgeneral BD-R, by referring to a pit string recorded in the form of aunique pattern in an area, such as the PIC region of the optical disc.

[0045] Accordingly, in the case of an optical disc apparatus adapted toplay back a BD-ROM or BD-R recorded with the above described physicalmark information, for example, a BD-ROM player including an opticalpickup 20, a VDP system 21, and a D/A converter 22, as shown in FIG. 8,the BD-ROM player detects and identifies the physical mark informationat the initial stage of a typical servo operation thereof carried outwhen an optical disc is loaded, detects and identifies the unique formatof data read out from the data area of the optical disc during a datareproduction operation thereof, thereby determining whether or not thedata was illegally duplicated on the optical disc, so as to perform aplayback restricting operation by stopping playback of the optical discin accordance with the result of the determination. These operationswill be described in detail hereinafter.

[0046]FIGS. 9a and 9 b are flow charts illustrating a method forrestricting playback of an optical disc in an optical disc apparatus inaccordance with an exemplary embodiment of the present invention.

[0047] In the optical disc apparatus shown in FIG. 8, a typical focusingand tracking servo operation is carried out by the VDP system 21 when anoptical disc is loaded in the optical disc apparatus (S10), as shown inFIG. 9a.

[0048] At the initial stage of the servo operation, the VDP system 21accesses a disc identification area preceding a lead-in area, in thedata area, in the lead-out area, or in an area following the lead-outarea of the information area of the optical disc, to detect and identifyphysical mark information recorded in the disc identification area. Forexample, where it is determined that the physical mark informationcorresponds to ID information associated with BD-ROM (S11), the VDPsystem 21 determines that the loaded optical disc is a BD-ROM.

[0049] Subsequently, the VDP system 21 searches a data area assigned toan information area of the optical disc, and performs a datareproduction operation for reading out data recorded in the data area,and reproducing the read-out data (S12). Where the data read out in theabove described procedure has a format unique to BD-ROM, that is, theread-out data is BD-ROM format data (S13), the VDP system 21 determinesthe loaded disc to be a normal BD-ROM, and continues the datareproduction (playback) operation (S14).

[0050] On the other hand, where the read-out data does not have theformat unique to BD-ROM, that is, it is not BD-ROM format data, the VDPsystem 21 determines that there is an error in determining the type ofthe optical disc (S15). In this case, the VDP system 21 stops the datareproduction (playback) operation or performs the disc determiningoperation again.

[0051] Where the physical mark information recorded in the discidentification area does not correspond to BD-ROM ID information, forexample, where information recorded in accordance with a format uniqueto BD-RE is detected (S20), the VDP system determines the loaded opticaldisc to be BD-RE.

[0052] The VDP system 21 searches the data area assigned to theinformation area, and then performs a data reproduction operation forreading out data recorded in the data area, and reproduces the read-outdata (S21). Where the data read out has a format unique to BD-RE, thatis, the read-out data is BD-RE format data (S22), the VDP system 21determines the loaded optical disc to be a normal BD-RE, and continuesthe data reproduction (playback) operation (S23).

[0053] On the other hand, where the read-out data does not have theformat unique to BD-RE, for example, where it is BD-ROM format data, theVDP system 21 determines that BD-ROM data was illegally duplicated on aBD-RE, and displays a report message, while performing a playbackrestricting operation to stop the data reproduction operation (S24).

[0054] Where BD-R ID information is detected from the physical markinformation recorded in the disc identification area (S30), the VDPsystem 21 determines the loaded optical disc to be BD-R. In this case,the VDP system 21 searches the data area assigned to the informationarea, and then performs a data reproduction operation for reading outdata recorded in the data area, and reproducing the read-out data (S31).

[0055] Where it is subsequently determined that the data read out has aformat unique to BD-ROM, that is, the read-out data is BD-ROM formatdata (S32), the VDP system 21 determines that BD-ROM data was illegallyduplicated on a BD-R, and displays a report message, while performing aplayback restricting operation to stop the data reproduction operation(S33).

[0056] On the other hand, where the read-out data does not have theformat unique to BD-ROM, for example, where it is BD-RE format data orBD-R format data, the VDP system 21 determines that the loaded opticaldisc is a normal BD-R, and continues the data reproduction operation(S34).

[0057] Further, although BD-ROM format data is recorded in the data areaof a BD-R disc, separate copyright allowance information mayadditionally be recorded, and a normal data reproduction operation canbe carried out if it can be determined that duplication of data wasauthorized, based on the copyright allowance information.

[0058] As apparent from the above description, exemplary embodiments ofthe present invention provide a high-density, optical disc, such asBD-ROM, capable of preventing unauthorized duplication of data streams,written thereon, onto a BD-RE or BD-R, and a method for restrictingplayback of high-density optical discs duplicated illegally in anoptical disc apparatus.

[0059] Although the exemplary embodiments of the invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

We claim:
 1. A recording medium including recorded data, comprising: aninformation area for recording disc management information and/or data,the information area includes a lead-in area, a data area, and alead-out area; and physical mark information, recorded as a wobbled pitpattern in an area preceding the lead-in area, in the lead-in area, inthe data area, in the lead-out area, or in an area following thelead-out area of the information area.
 2. A recording medium accordingto claim 1, wherein the physical mark information is not in a writablearea.
 3. A recording medium according to claim 1, wherein the physicalmark information includes information identifying the recording mediumtype.
 4. A recording medium according to claim 1, wherein the physicalmark information is recorded as a pattern representing duplicationpreventing information.
 5. A recording medium according to claim 1,wherein the physical mark information is recorded as mark/space withrespect to a high-frequency-modulated groove.
 6. A recording mediumaccording to claim 5, wherein the mark/space are aligned with oneanother in each recording field of a high-frequency-modulated groove. 7.A recording medium according to claim 5, wherein the physical markinformation is recorded as at least one mark/space, wherein eachmark/space pair include a mark and a space each having an variablelength.
 8. A recording medium according to claim 7, wherein each markand space of the mark/space pairs are aligned with one another in eachrecording field of a high-frequency-modulated groove.
 9. A recordingmedium according to claim 8, wherein a length of the mark and space ofeach recording field is determined to be a different length inaccordance with a data value associated with the recording field.
 10. Arecording medium according to claim 1, wherein the physical markinformation is detected at an initial stage of a servo operation carriedout in an optical disc apparatus, separately from a decoding operationto be carried out in the optical disc apparatus.
 11. A recording mediumaccording to claim 1, wherein the physical mark information is in anarea of the disc where writing of data is impossible after manufactureof the recording medium, the physical mark information is a BD-ROMidentification area (ROMID), and the recording medium is a read-onlyrecording medium.
 12. A recording medium according to claim 1, whereinthe physical mark information is in an area of the disc where writing ofdata is possible only once after manufacture of the recording medium,the physical mark information is a BD-R identification area (RID), andthe recording medium is a write-once recording medium.
 13. A method offorming a recording medium, comprising: forming an information area forrecording disc management information and/or data, the information areaincludes a lead-in area, a data area, and a lead-out area; and formingphysical mark information as a wobbled pit pattern in an area precedingthe lead-in area, in the lead-in area, in the data area, in the lead-outarea, or in an area following the lead-out area of the information areaof the information area.
 14. A method of claim 13, wherein the physicalmark information is formed as a pattern representing duplicationpreventing information.
 15. A method of claim 13, wherein the physicalmark information is formed as mark/space with respect to ahigh-frequency-modulated groove
 16. A method of claim 15, wherein themark/space are aligned with one another in each recording field of ahigh-frequency-modulated groove.
 17. A method of claim 1, wherein thephysical mark information is formed to be detected at an initial stageof a servo operation carried out in an optical disc apparatus,separately from a decoding operation to be carried out in the opticaldisc apparatus.
 18. A method of claim 1, wherein the physical markinformation is formed in an area of the disc where writing of data isimpossible after manufacture of the recording medium, the physical markinformation is a BD-ROM identification area (ROMID), and the recordingmedium is a read-only recording medium.
 19. A method of claim 1, whereinthe physical mark information is in an area of the disc where writing ofdata is possible only once after manufacture of the recording medium,the physical mark information is a BD-R identification area (RID), andthe recording medium is a write-once recording medium.
 20. A method ofreproducing data from a recording medium, comprising: utilizing physicalmark information to control reproduction of the recorded data, whereinphysical mark information has been recorded as a wobbled pit pattern inan area of the recording medium.
 21. A recording medium according toclaim 20, wherein the physical mark information has been recorded as apattern representing duplication preventing information.
 22. A recordingmedium according to claim 20, wherein the physical mark information hasbeen recorded as mark/space with respect to a high-frequency-modulatedgroove
 23. A recording medium according to claim 22, wherein themark/space are aligned with one another in each recording field of ahigh-frequency-modulated groove.
 24. A method of claim 20, wherein thephysical mark information is detected at an initial stage of a servooperation carried out in an optical disc apparatus, separately from adecoding operation to be carried out in the optical disc apparatus. 25.A method of claim 20, wherein the physical mark information isreproduced from an area of the disc where writing of data is impossibleafter manufacture of the recording medium, the physical mark informationis a BD-ROM identification area (ROMID), and the recording medium is aread-only recording medium.
 26. A method of claim 20, wherein thephysical mark information is reproduced from an area of the disc wherewriting of data is possible only once after manufacture of the recordingmedium, the physical mark information is a BD-R identification area(RID), and the recording medium is a write-once recording medium.
 27. Amethod of recording data on a recording medium, comprising: recordingthe data in an information area, which includes a lead-in area, a dataarea, and a lead-out area; and recording physical mark information as awobbled pit pattern in an area of the information area, which controlsreproduction of the recorded data.
 28. A recording medium according toclaim 27, wherein the physical mark information is recorded as a patternrepresenting duplication preventing information.
 29. A recording mediumaccording to claim 27, wherein the physical mark information is recordedas mark/space with respect to a high-frequency-modulated groove
 30. Arecording medium according to claim 29, wherein the mark/space arealigned with one another in each recording field of ahigh-frequency-modulated groove.
 31. A method of claim 27, wherein thephysical mark information is recorded to be detected at an initial stageof a servo operation carried out in an optical disc apparatus,separately from a decoding operation to be carried out in the opticaldisc apparatus.
 32. A method of claim 27, wherein the physical markinformation is recorded in an area of the disc where writing of data isimpossible after manufacture of the recording medium, the physical markinformation is a BD-ROM identification area (ROMID), and the recordingmedium is a read-only recording medium.
 33. A method of claim 27,wherein the physical mark information is recorded in an area of the discwhere writing of data is possible only once after manufacture of therecording medium, the physical mark information is a BD-R identificationarea (RID), and the recording medium is a write-once recording medium.34. An apparatus for reproducing data from a recording medium, saidapparatus utilizing physical mark information to control reproduction ofthe recorded data, wherein the physical mark information has beenrecorded as a wobbled pit pattern in an area of the recording medium.35. An apparatus of claim 34, wherein the physical mark information hasbeen recorded as a pattern representing duplication preventinginformation.
 36. An apparatus of claim 34, wherein the physical markinformation has been recorded as mark/space with respect to ahigh-frequency-modulated groove
 37. An apparatus of claim 36, whereinthe mark/space are aligned with one another in each recording field of ahigh-frequency-modulated groove.
 38. An apparatus of claim 34, whereinthe physical mark information is detected at an initial stage of a servooperation carried out in an optical disc apparatus, separately from adecoding operation to be carried out in the optical disc apparatus. 39.An apparatus of claim 34, wherein the physical mark information isreproduced from an area of the disc where writing of data is impossibleafter manufacture of the recording medium, the physical mark informationis a BD-ROM identification area (ROMID), and the recording medium is aread-only recording medium.
 40. An apparatus of claim 34, wherein thephysical mark information is reproduced form an area of the disc wherewriting of data is possible only once after manufacture of the recordingmedium, the physical mark information is a BD-R identification area(RID), and the recording medium is a write-once recording medium.